Necromancer

Necromancers are enemies who are extremely dangerous due to their ability to spawn Skeleton minions and shoot fireballs.

Tips:

Don't have easily hittable wooden objects on your walls, if they get hit by a fire ball they will fuel the fire to the point where it could burn down a stone wall,

There is a trick in which you place your town hall in a random location in the map so very little enemies will attack your town, DON'T DO THIS! When skeletons spawn anywhere on the map they will make a beeline straight for the necromancer, having a town hall out in the middle of nowhere will simply allow the Necromancer to gather a HUGE army before attacking you.

Make sure you have tall enough walls, if he manages to snipe any wooden structure or object in your base it could set the whole place on fire.